Abstract: An engine exhaust system comprising an exhaust pipe routing an exhaust flow through a bend, and being in fluid communication with a catalyst downstream of the bend. An injector mounted to the exterior of the exhaust pipe, the injector with a tip disposed within the exhaust pipe at the bend, for injecting liquid reductant into the exhaust pipe. A shield member mounted in the exhaust pipe, the shield member comprising a generally tubular or frustoconical structure having a proximal and a distal end, the proximal end being disposed such that the injection tip is inside the shield member, the distal end being disposed towards a centerline of the exhaust pipe. A vane mounted in relation to the shield member, the vane being arranged to direct a proportion of exhaust flow from upstream of the bend in a substantially arcuate path into the proximal end of the shield member.

Abstract: An engine exhaust system comprising an exhaust pipe routing an exhaust flow through a bend, and being in fluid communication with a catalyst downstream of the bend. An injector mounted to the exterior of the exhaust pipe, the injector with a tip disposed within the exhaust pipe at the bend, for injecting liquid reductant into the exhaust pipe. A shield member mounted in the exhaust pipe, the shield member comprising a generally tubular or frustoconical structure having proximal and distal end, the proximal end being disposed such that the injection tip is inside the shield member, the distal end being disposed towards a centerline of the exhaust pipe. A vane mounted in relation to the shield member, the vane being arranged to direct a proportion of exhaust flow from upstream of the bend in a substantially arcuate path into the proximal end of the shield member.

Abstract: An exhaust system for use with a combustion engine is disclosed. The exhaust system may have an exhaust passage configured to receive a flow of exhaust from the combustion engine, and an oxidation catalyst disposed within the exhaust passage. The exhaust system may also have a fuel injector configured to selectively inject fuel into the exhaust at a location upstream of the oxidation catalyst, a temperature sensor configured to generate a signal indicative of a temperature of exhaust flowing through the exhaust passage, and a controller in communication with the fuel injector and the temperature sensor. The controller may be configured to make a determination based on the signal that an oxide layer has formed on the oxidation catalyst, and to regulate operation of the fuel injector to inject fuel and reduce the oxide layer based on the determination.